If you're debating between living a life in the city or the suburbs, consider this new research from the American Geophysical Union: Scientists reported evidence this month at a meeting in San Franscisco that suburban communities have graver environmental impacts than was previously known. Today suburbs comprise an area up to four times the size of Ohio, and they're expanding rapidly.

“The suburban landscape is large, and it’s growing,” Jennifer Jenkins, a scientist from the University of Vermont, told Knight Ridder. “There’s this enormous land surface that’s falling through the cracks.”

The biggest problem is damage to watersheds, according to coverage in USA Today: Nitrogen runoff from suburban septic tanks is polluting surrounding lakes, streams and waterways. Nitrogen causes algae blooms that in turn bedevil fisheries. Meanwhile, the fresh rainwater that usually cleanses and replenishes these waterbodies is blocked by an ever-expanding amount of paved surfaces.

A study last year found that more than 43,000 square miles of the United States is currently paved or covered with buildings. As a result, the rain water doesn't trickle down, but slides off the pavement in large volumes, rushing into soil and streams and causing erosion.

Photo credit: Usatoday.com, Bill Bowden, AP